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When driving the paralleled LED strings, the large forward tolerance across the LED will result in the current non-uniformly distributed between each string, which causes LEDs to be overdriven and influence the lifespan. This paper presents a single inductor multiple outputs parallel string LED driver with time multiplexing control schemes. Two kinds of pulse-width modulation schemes are presented...
Considerable progress has been made in recent years in the study of the Earth's gravitational field by observing the motion of satellites in low altitude orbits. However, such observations are hampered by the aerodynamic drag caused by the residual atmosphere, which modifies the orbits of these satellites in an unpredictable way. In order to overcome this problem, an on-board propulsion system with...
The cusped field thruster represents a new type of electric propulsion device incorporating cusped magnetic field profiles that keep high energy ions away from channel walls and mitigate erosion. Thus its lifetime will be longer compared with so me other type of electric propulsion devices. Recently, the cusped field thruster has been paid much attentions by many organizations, such as Thales Research...
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